"Kurtz is a disturbing symbol of madness and despair, but he does not dominate the novel.
Kurtz is definitely a disturbing symbol in Heart of Darkness, embodying the gloom, the despair, the "impenetrable darkness" of the unknown jungle, the darkness inherent in all men's hearts but he does not dominate the novel. It is Marlow's perception, his ever changing understanding of the darkness and its many elements from afar and up close, that fills the novel, creates its many layers. It is his indeed this intense journey to Kurtz, Marlow's journey of discovery on all levels that dominates Joseph Conrad's novella, Heart of Darkness.
Marlow's journey to Kurtz has many levels, each profound and meaningful. Perhaps one of the most interesting aspects of the novel is Conrad's powerful indictment of the evils of imperialism. - "The dreams of men, the seeds of men, the germs of empires." His account in HOD perhaps reflects the savage repressions carried out in the Congo by the Belgians in one of the largest acts of genocide committed up to that time. And yet, Marlow, the central character in the novel seems to be simultaneously a good liberal identifying humanity within some of the natives, realising that they are in fact human, and a racist at the same time, that the natives are still but mere savages. -- "a savage who is no more account than a grain of sand in a black Sahara." Marlow is simultaneously a good liberal and a racist, and a man struggling quite consciously with both perspectives. It is Conrad's subtly in his treatment of such matters that allows us to make our own judgements, our own interpretations of Marlow's river journey to Kurtz.
On the way up the Congo to Kurtz, Conrad takes us on a ride using the powerful writing tool of symbolism. The symbols becoming a vehicle that carries us, the audience, from stop to stop, Marlow's journey becoming an evaluation of the darkness contained inside the hearts of mankind.